Aneurysmal size reduction in the Kommerell diverticulum by stent graft-based therapy

Kommerell diverticulum (KD) with an aberrant subclavian artery is a rare congenital anomaly that often resembles a saccular aneurysm. Open surgery is the traditional treatment; however, recent reports have suggested success with endovascular or hybrid approaches. This study aimed to show the results of stent graft-based treatment and demonstrate the aneurysmal reduction rate in KD. Five patients with KD underwent stent graft-based therapy at the Osaka Metropolitan University Hospital between May 2009 and February 2024. Patient data and KD measurements were retrospectively analyzed using computed tomography scans. Two indices were measured to assess the size of the KD: (I) the distance from the tip of the KD to the opposite aortic wall (DAW), which is often used to assess KD size; (II) the height of the KD from the original virtual normal aortic wall, as in the evaluation of saccular aneurysms. The mean observation period after surgery was 62.4±36.9 months. Postoperative remodeling of the KD was assessed in these five cases. One patient underwent 1-debranch thoracic endovascular aortic repair, and four patients underwent the frozen elephant trunk (FET) technique via median sternotomy. On average, DAW was reduced to 76.1%±9.5% and the height of KD, the height of the protrusion from the normal aortic wall, was reduced to 31.0%±23.8%. None of the five cases required rehospitalization or reintervention. None of the patients died, and the KD was greatly reduced in size. Treatment using stent grafts greatly reduced the size of the KD. Decompression of KD is likely to lead to remodeling of the aortic wall, which constitutes KD.